The invention relates to a control device, in particular for a motor vehicle, having an actuator which can be activated manually, and having an arresting element which is designed to exert a force on the actuator as a function of control signals.
Such control devices are often used to input data into electronic devices and are thus known. In order to activate the device, the user firstly selects a desired function, for example by activating the actuator by applying pressure. Then, the controlled variable of the selected function is set by means of a rotary activation of the actuator. The force which is necessary for the rotary activation is variable depending on the function selected, and is generated using the arresting element. For this purpose, the arresting element has an electric motor which exerts the arresting force on the actuator and thus permits the user of the control device to be provided with so-called haptic feedback. The force is dependent on the functional level selected and the associated rotary torque characteristic curves which are stored in a memory and can be freely programmed for this purpose.
Thus, it is possible, for example, to program a countertorque which is proportional to the rotational speed, for example for setting frequencies or dimming, to program latching steps, for example for volume control, to program haptic marks in order to indicate specific positions of the actuator, for example for air conditioning, or even to program an increasing countertorque in order to indicate minimum and maximum positions. The electric motor which is used as an arresting element is even capable of accelerating the activation element in the direction of the activation force so that the activation element merely has to be pressed with the finger at an appropriate programming of the memory in order to perform a control operation, or can signal, by vibrating, that a limiting value has been exceeded. As a result, a single control device can be used for a variety of application areas. Therefore, the control device is preferably used for setting the various types of equipment and devices, such as navigation systems and air conditioning systems, which are found in a motor vehicle.
In control devices which are designed in this way it is disadvantageous that the force which is exerted by the arresting element, i.e. the rotating sensation which has been set for the user, cannot be perceived directly. To perceive the sensation, the user must firstly activate the actuator and xe2x80x9cfeel outxe2x80x9d the rotating sensation which has been set, for example the number of latching steps. Of course, consideration has already been given to the possibility of defining the value of the set function in its basic setting to an average value which can then be corrected upwardly or downwardly on an individual basis by the user, but this arrangement does not permit any conclusions to be drawn concerning the range or graduation of the values which can be set.
Furthermore, it is also known to represent the set function and the set value graphically in a display. In such a case, a minimum value which can be set or a maximum value which can be set is usually apparent but it is not possible to draw conclusions concerning the actuator which is to be activated. Furthermore, the display is often arranged at a central location and connected to a plurality of control devices, the assignment of said control devices being frequently felt to be very complicated.
The invention is based on the problem of providing a control device of the type mentioned at the beginning in such a way that control is made easier, in particular the intention here is that the selection possibilities should be readily apparent without firstly having to set all the possible values on a trial basis in order to detect them.
This problem is solved according to the invention by means of a display for representing information as a function of the control signals for exerting the force on the actuator. As a result, a visual display which is directly apparent to the user can be provided directly as a function of the force which acts on the actuator by way of the arresting element, and thus as a function of the rotating sensation which can be perceived by the user. In particular, the number of possible latching steps or the range between a minimum value and a maximum value can be represented for this purpose. Therefore, the user does not need to determine the range of the possible settings by trying them out, but instead can relate the value which has been set directly to the range of the possible values.
The display can have an alphanumeric or symbolic representation of the rotating sensation which is imparted by means of the arresting element. However, an embodiment of the invention in which the display has a row of illuminable elements with sections which can be driven individually is particularly advantageous. The row of illuminable elements can be used to represent, firstly, the minimum and maximum position, and secondly also latching steps, by means of an appropriate number of driven sections or an infinitely variable setting using a row of illuminable elements which can be driven continuously. As a result, the relationship between the display and the rotating sensation is directly apparent to the user, and therefore requires no further indications.
In this context it is also particularly favorable if the display has a plurality of LEDs. This makes it possible to provide a display which can be read reliably and without difficulty and which is also easy to manufacture and available in different shapes and illuminated colors. Furthermore, it is possible to use a single LED to set different illuminated colors depending on the way in which it is driven, and thus to highlight certain values visually, for example,
One embodiment of the invention is particularly advantageous by virtue of the fact that the display is arranged on the actuator. The association between the actuator and the force which is applied by means of the arresting element is thus readily apparent. At the same time, the actuator and the display can be manufactured as one structural unit, thus making it easier to install.
One development of the invention can be used particularly easily by virtue of the fact that the actuator has a rotary actuating element. A rotary actuating element can be activated comparatively sensitively and precisely. At the same time, its permissible rotational angle can be adapted in an optimum way to the respective set function by means of the arresting element; for example a small number of latching steps only require a small rotational angle in contrast to a proportional setting, which is easier to use the greater the maximum rotational angle selected. When this is the case, the display also makes it possible to visualize the angular position of the possible range of rotational angles.
In this context, an embodiment of the invention in which the display is positioned on the circumference of the rotary actuating element is also particularly simple. As a result of this, a compact embodiment is obtained, which can also be provided as one structural unit. The display can thus be arranged either in such a way that it rotates together with the rotary actuating element or is fixed, and it can, for example, be covered by a transparent region of the rotary actuating element. The rotational embodiment of the display makes it possible not only to represent the force applied by the arresting element but also to read the set value by means of the rotational angle of the display against a fixed background.
Another advantageous development of the invention is also provided by arranging the display on an end face of the actuator. As a result, the display can be read without difficulty and arranged, for example, in this case in a central recess or underneath an essentially transparent section of the actuator, in which case the display can be designed in such a way that it rotates with the actuator or is fixed. The display can be arranged in a space-saving manner on the end face and can thus also be read during the activation process.
A particularly versatile embodiment of the invention is provided if the display is at the same time providing to represent the position of the actuator. In addition to a representation of all the possible positions of the actuator, such as in particular the number of latching steps or the maximum value, it is also possible to read the value which has been set at a given moment. This can be achieved, for example, by visually highlighting the current value, for example by changing the color of the corresponding LED. The integrated representation of both types of information enables reading errors to be largely ruled out and further simplifies the manufacturing process.
A particularly practical development of the invention is obtained if the control device has a display for representing a selected function. As a result, it is possible to dispense with further means for representing the selected function. In particular if a plurality of control devices are used, the user does not need to decide initially which control device is assigned to the respective function but instead can discern this directly from the display. As a result, the control device is simultaneously a structural unit and a functional unit which can be operated easily without additional means.
For this purpose, the display could permit symbols, for example pictograms, to be represented. But on the other hand, a development of the invention in which the display has an LCD is particularly versatile. As a result, the control device can be adapted to any desired purposes of use. The desired information can be entered here individually so that virtually any desired number of different functions can be activated with a single control device. At the same time, this will permit both later installation of further functions and adaptation to the changing state of the art to be performed without difficulty, possibly even by the end user.